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Coral reef recovery dynamics in a changing world

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Abstract

Coral reef ecosystems are degrading through multiple disturbances that are becoming more frequent and severe. The complexities of this degradation have been studied in detail, but little work has assessed characteristics that allow reefs to bounce back and recover between pulse disturbance events. We quantitatively review recovery rates of coral cover from pulse disturbance events among 48 different reef locations, testing the relative roles of disturbance characteristics, reef characteristics, connectivity and anthropogenic influences. Reefs in the western Pacific Ocean had the fastest recovery, whereas reefs in the geographically isolated eastern Pacific Ocean were slowest to recover, reflecting regional differences in coral composition, fish functional diversity and geographic isolation. Disturbances that opened up large areas of benthic space recovered quickly, potentially because of nonlinear recovery where recruitment rates were high. The type of disturbance had a limited effect on subsequent rates of reef recovery, although recovery was faster following crown-of-thorns starfish outbreaks. This inconsequential role of disturbance type may be in part due to the role of unaltered structural complexity in maintaining key reef processes, such as recruitment and herbivory. Few studies explicitly recorded potential ecological determinants of recovery, such as recruitment rates, structural complexity of habitat and the functional composition of reef-associated fish. There was some evidence of slower recovery rates within protected areas compared with other management systems and fished areas, which may reflect the higher initial coral cover in protected areas rather than reflecting a management effect. A better understanding of the driving role of processes, structural complexity and diversity on recovery may enable more appropriate management actions that support coral-dominated ecosystems in our changing climate.

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Acknowledgments

We thank Stefan Walker for assistance in compiling literature for this study. The study was supported through fellowships to N.A.J.G. from the Australian Research Council and the Queensland Smart Future Fund. The manuscript was improved through comments from Morgan Pratchett and Josh Cinner.

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Correspondence to N. A. J. Graham.

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Communicated by Environment Editor Prof. Rob van Woesik

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Fig. S1

Mean annual rate of change in per cent coral cover recovery calculated for (a) all sites, (b) omitting the Seychelles data which contributed a large number of sites to the data set (8) and (c) when including one site per study (n = number of sites; error bars = 95% bootstrapped CI). (EPS 7 kb)

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Graham, N.A.J., Nash, K.L. & Kool, J.T. Coral reef recovery dynamics in a changing world. Coral Reefs 30, 283–294 (2011). https://doi.org/10.1007/s00338-010-0717-z

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